In order to make it easier to understand the following description, we shall first define some of the terms used below.
A customer and a subscriber refer to a person or community that buys and uses an intelligent network service.
An operator refers to a person or community that creates a service meeting the requirements set by the customer or subscriber.
A manufacturer refers to a person or community that manufactures the equipment and software with which the operator creates an intelligent network service.
Fast developments in telecommunications have enabled operators to provide various services for users. Network architecture offering advanced services is called an intelligent network, generally abbreviated as IN. IN architecture can be applied to most telecommunication networks, such as Public Switched Telephone Networks (PSNT), mobile communication networks, Packet Switched Public Data Networks (PSPDN), Integrated Services Digital Networks (ISDN) and Broadband Integrated Services Digital Networks (B-ISDN). Irrespective of network technology, the object of IN architecture is to facilitate creation, control and management of new teleservices. With regard to present IN specifications, reference is made to Advanced Intelligent Network, Release 1 (AIN Rel.1) by Bellcore and Capability Set 1 (CS-1) by CCITT.
IN architecture is illustrated by FIG. 1, in which physical entities are represented by as rectangles or circles, and functional entities, ovals. Signaling connections are indicated by broken lines, and actual transport, which is, e.g., speech, by solid lines. Optional functional entities are indicated by a broken line. The signaling network shown in the figure is a network according to Signaling System No. 7 (SS7, a known signaling system described in the blue book Specifications of Signaling System No. 7, Melbourne 1988 of CCITT (now: ITU-T)).
First the architecture in the physical plane of an intelligent network will be described. Subscriber Equipment (SE), such as a phone, computer or telefax, is switched either directly to a Service Switching Point (SSP) or to a Network Access Point (NAP).
The service switching point (SSP) offers the user access to the network and takes care of all the necessary selections. The (SSP) is also able to detect any requests for service in the intelligent network. Operatively, the (SSP) contains call management and service selection functions.
The network access point (NAP) is a conventional exchange (e.g. a DX 220 exchange by the applicant) that contains a Call Control Function (CCF) and is able to distinguish between conventional calls and calls needing the services provided by the intelligent network and to route the latter to the appropriate (SSP).
The Service Control Point (SCP) contains the service logic programs used for providing intelligent network services.
The Service Data Point (SDP) is a database containing data on the customer and network, the data being used by the service logic programs of the SCP to provide individualized services. The SCP can use the services of the SDP either directly or through a signaling network.
An Intelligent Peripheral (IP) provides special-purpose functions, such as announcements and voice and multiple choice detection.
A Service Switching and Control Point (SSCP) comprises an SCP and an SSP in a single node (i.e., if an SSP node shown in the figure comprises both SCF and SDF entities, it is an SSCP).
The functions of a Service Management Point SMP comprise management of the database (SDP), control and testing of the network, and collection of network information. It can be connected to all other physical entities.
A Service Creation Environment Point (SCEP) is used for defining, developing and testing the IN services, and for supplying the services to the SMP.
An Adjunct (AD) corresponds operationally to the service control point (SCP) but is connected directly to an SSP by a high-speed data link (e.g., ISDN 30B+D connection) rather than through the common channel signaling network SS No. 7.
A Service Node (SN) can control IN services and transfer data to and from the users. It communicates directly with one or more SSPs.
A Service Management Access Point (SMAP) is a physical entity that provides certain users with access to the SMP.
To define the function of the different modules in the intelligent network and the restrictions relating to them, the standards (CS-1) also present the intelligent network as a four-plane Intelligent Network Conceptual Model. One layer of the model forms a so-called Distributed Functional Plane DFP, which describes the intelligent network as functional units in accordance with the above CS-1 standard. The following is a description of these functional units, the locations of which are shown in FIG. 1.
The functions relating to call control are SSF, SRF, CCF and CCAF.
A Service Switching Function (SSF) interconnects a Call Control Function (CCF) and a Service Control Function (SCF) by allowing the service control function (SCF) to control the call control function (CCF).
A Specialized Resources Function (SRF) provides specialized resources needed for implementing IN services. Examples for these are changes in protocol, speech detection, voice messages, etc.
The call control function (CCF) refers to conventional call and connection establishment. A Call Control Agent Function (CCAF) provides the user with access to the network.
The functions relating to service control are (SCF) and SDF. A Service Control Function SCF comprises the IN service logic and attends to service-bound processing. A Service Data Function (SDF) provides access to service-bound and network information, and allows consistent checking of information. The SDF hides from the SCF the actual implementation of the information and offers the SCF a logical view of the information.
The functions relating to management are a Service Creation Environment Function (SCEF), Service Management Function (SMF) and Service Management Access Function (SMAF). The SMF comprises supervision of management, maintenance and location of the services; the SMAF provides a connection to the SMF; and the SCEF makes it possible to define, develop and test IN services and supply them to the SMF.
A request for service made by, a calling party typically comprises an act of picking up the receiver and/or a certain series of numbers. The call control function (CCF) has no service information, but it is programmed to identify the requests for service. The CCF interrupts the call set-up for a moment and informs the service switching function (SSF) of the state of the call. The function of the SSF is to interpret the request for service and the information on the state of the call, to form a standardized request for service and to send the request to the SCF. The SCF receives the request and decodes it. After this, it forms, encodes and sends a standardized response to the SSF. The formation of a response may comprise encoding of complicated service logic, starting of a Prompt and Collect Sequence, or a request to different SDFs. The SSF decodes and interprets the response sent by the SCF. It then gives the CCF accurate instructions for performing the preparation process. In accordance with the IN standard CS-1, the call control function (CCF) always bears full responsibility for the condition and control of local links.
When a response is sent to an SSF, the service control function (SCF) may have to participate in a conversation between a calling user and an end user. This normally takes place in the form of the above prompt and collect sequence, which the SCF authorizes the SRF to perform. Typically, the SCF instructs the SSF to connect the calling user or end user to a suitable physical source by using the SRF. The source may be e.g. a voice message system. The SCF instructs the SRF in the required prompt and collect sequence and subsequently temporarily `freezes` the call processing. The SRF activates the prompt and collect sequence and participates in the conversation between the calling user and the end user. The response, which may be, e.g., an individual ID number, is encoded and returned to the SCF, and the voice connection with the SRF is terminated. After this, the SCF continues its service control sequence.
The above is a brief description of an intelligent network offering services implemented in accordance with the present invention. For more specific details, see, e.g., the ITU-T recommendations Q.121X or the Bellcore recommendations AIN.
An intelligent network can offer a large number of different services. The services include, e.g., freephone and Account Card Calling (ACC), which means that the user can phone from any phone to any number by inserting the number and PIN of his credit card before he inserts the telephone number. A graphical user interface for creating IN services is presented in patent application WO 92/11603. In the method of the document, a program record containing desired characteristics is customized separately for each customer, and the record is stored in a database located in the SCP so that it can be called to direct the call when the SSP announces that a predefined trigger condition is met. A situation like this where control of the SCP is required may be, e.g., a call destined to or dialed from a specific number. A program record comprises primitives (basic units of a program), which in a graphical user interface are represented by nodes. The operator determines the relations between the primitives by lines connecting the nodes. Each separate graph consisting of nodes and lines connecting them corresponds to a separate program record stored in the database. Problems in this known method are a need for a graphical user interface and the high costs involved in the solution. A subscriber-specific service cannot be created without expensive special equipment and programs by which the graphical representation of the service is converted into a code executed through an intermediate step and stored in the database. Further, even if two subscribers buy the same service, a separate program record will have to be created for each subscriber. This increases the need for capacity in the database and the work load of the operator.
An improvement to the above method is presented in patent application WO 94/05111, which introduces the concept of a service template. The operator or manufacturer can design a template for the best selling services. When a customer subscribes to a service, the operator creates the service by loading a service according to the template to the display of a graphical user interface and by making such customer-specific additions or modifications to the service that are necessary for creating the service requested by the customer. The service customized in this manner is then converted into a code to be executed and stored in the database of the (SCP). Although in the method the operator need not create a service logic program for each customer `starting from scratch`, a separate code-containing program record will have to be created for each customer and stored in the database. The other drawbacks of the earlier method also remain unsolved.